The present invention relates to a bi-directional rotation pneumatic cutting machine and particularly to a pneumatic cutting machine capable of rotating in the positive direction or the reverse direction depending on different requirements to direct sparks, cutting debris or dusts generated in the cutting process in a desired direction.
Conventional cutting machines generally rotate in an unidirectional manner. As cutting machines are designed in many different types, they are widely used in many industries such as iron work, machinery, wood working, molding, automobiles and motorcycles, repairs and maintenance, glass fibers, electronics, and the like.
The unidirectional rotation cutting machine mainly includes an operation section and a grasp section. The operation section has a fastening mechanism. FIG. 1 illustrates a typical fastening mechanism for pneumatic cutting machines. As shown in the drawing, its operation section has an output shaft 6 extending outwards. The output shaft 6 has a rear section to couple with a bearing 7 and a front section to screw a coupling head 1. The coupling head 1 is fastened by a fastener 2. When in use, a cutting tool 4 is sandwiched and anchored between the coupling head 1 and the fastener 2. The output shaft 6 is driven by a driving mechanism to rotate at high speed to drive the cutting tool 4 to rotate in one direction. When the unidirectional cutting machine performs cutting operation, sparks, debris, powders or dusts are inevitably generated. The sparks may spew to the surrounding and cause fire when inflammable goods are around. Dusts produce environmental pollution. The debris of the cutting material scatter around and may cause severe hazards to the health and safety of operators. To remedy these concerns, a mask 9 is usually installed above the coupling head 1 that has an interference-avoiding section 191 to enable users to drive or couple the fastener 2.
Moreover, due to conventional cutting machines rotate in one direction, when cutting a narrower working piece or corners, the grasp section is constrained due to design limitation and allows only surface machining to be performed on the working piece. Some corners cannot be machined smoothly by the conventional cutting machines, and operators have to adopt other operating gestures or approaches to do machining operation. Those abnormal operation methods often affect cutting quality and produce defects on the machining surface.
The primary object of the invention is to resolve the aforesaid disadvantages and overcome the drawbacks of the prior art. The invention has reverse threads on an outer wall of one end of an anchor member and positive threads on its interior to enable the invention to rotate positively or reversely according to different requirements. Thus sparks, grinding debris or dusts generated in the cutting process may be directed in a desired direction to avoid polluting operation environment or hurting people and working pieces.
In order to achieve the foregoing object, the bi-directional rotation pneumatic cutting machine of the invention includes an actuator in an operation section to drive an output shaft to rotate in both directions, and a fastening mechanism fastening to the output shaft. The fastening mechanism includes a coupling head which has reverse threads formed in the interior to couple with the output shaft. The coupling head further is coupled with an anchor member which has another reverse threads. The anchor member is run through by a fastener which has positive threads to fasten to another positive threads formed on the output shaft. By means of the fastening mechanism that has elements of positive and negative threads and may be fastened tightly with one another, the invention may rotate positively or reversely according to different requirements without loosening. And sparks, cutting debris or dusts generated in the cutting process may be directed in a desired direction without polluting the operation environment or hurting people and the working pieces.
The foregoing, as well as additional objects, features and advantages of the invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings.